public JsonResult OrderDetails(ShoppingCartModel model)
 {
     try
     {
         if (Session["USERNAME"].ToString() == null)
         {
             return(null);
         }
         else
         {
             List <OrderDetailsModel> orderDetails = model.getOrderDetails();
             return(Json(new { Result = "OK", Records = orderDetails }, JsonRequestBehavior.AllowGet));
         }
     }
     catch (Exception ex)
     {
         return(Json(new { Result = "OK", Message = ex.Message }));
     }
 }